Automatic block-signaling system for electric railways.



No. 873,468 PATENTED DEC. '10. 1907.

F TOWNSEND, DEGD.

J. J. TOWNSEND, ADMINISTRATOR, AUTOMATIC BLOCK SIGNALING SYSTEM FOR ELECTRIC RA ILWAYS.

2 snhmsawnm 1.

APPLICATION FILED JUNE 29, 1906.

WITNESSES: A MING-130m No. 873,4sa- PATENTED DEC. 10. 1907.

F. TOWNSEND, DEGD.

J. J. TOWNSEND, ADMINISTRATOR.

AUTOMATIC BLOCK SIGNALING SYSTEM FOR. ELECTRIC RAILWAYS.

APPLICATION FILED JUNE 29. 1906.

2 SHEETS-SHEET 2.

Fl G&.

WITNE SE8: MWM a- UNITED STATES PATENT OFFICE.

FITZHUGH TOWNSEND, OF NEW YORK, N. Y.; JOHN J. TOWNSEND, ADMINISTRATOKOF SAID FITZHUGH TOWNSEND, DECEASED, ASSIGNOR TO GENERAL RAILWAY SIGNAL COMPANY,

A CORPORATION OF NEW YORK.

AUTOMATIC BLOCK-SIGNALING SYSTEM FOR ELECTRIC RAILWAYS.

' f To all whom it may concern;

Be it known that I, FITZHUGH TOWNSEND,

' ,a citizen of the United States, residing-at New York city, county and State of New York, have invented an Automatic Block- 'Signaling System for Electric Railways, of

v which' the following is a specification.

My invention relates to an automatic block signaling system for electric railways where .the propulsion current is alternating, and,

broadly stated, consists in impressing a direct current upon each block section of the railway, and utilizing such direct current to control translating devices governing the'action of the signals.

The object of my invention is to decrease the cost of installation,- of such a signaling system, by doing away with the usual generator for the signaling. current and the necessary feeder therefrom.

A further object of my invention is'to provide means for controlling the action of the translating devices governing the si nals, by

direct current impressed upon the b ock sec- 7 illustrate my invention:

- Figure l- -illustrates a system where the di vrect current is impressed upon the block sectlons by means of thermo-generators; Flg. 2 1s an enlarged view showing the construc tion ofthe thermo-generators; Fig. 3is an enlarged view showing the construction of "'the' armature. of the rotary relay employed in l eo' Fig. 313', Fig. 4illustrates a system where the direct current is impressed upon the block sections by means of a battery, and a parallel typ'eof shielded relay em loyed; Fig. 5-is i i an enlarged view showing t e construction of the relay employed in Fig. 4; Fig. 6-is a 'f'view of a relay such as used in Fig. 4, with "three poles;

v, ig. 7is a plan view of the relay shown in Fig. 6.

-- Referring first to Fig. 1 5 indicates a gen- 5"' 0'"er tor of alternating current, 6, feeder therefrjm, 7, 8, tr'aflic rails divided into block sectioiis,"X, Y, Z. The rail 7 is divided into sections by means ofinsulators, 9, and the rail 8 Specification of Letters Patent.

Application filed June 29-1906. Serial No. 323-976.

the rail 8.

. v k Patented Dec. 10, 1907.

secured together at their joints, as, for in-' stance, a bar of bismuth secured to a bar of antimony, the whole series being connected across the track-way; also a heatingcoil,'11, carried around said bars so as toinclude a series of points of contact of the dissimilar metals.

I wish it understood that I do not limit myself to the employment of a thermo-generator, as I may use a battery, as shown in Fig. 4, or any other device for exciting a direct difference of potential between the rails 7 and 8. To produce the heating current used within the thermo-generator, and to furnish motor power for operating the signals, I make use of a transformer, 12, having itsprimary, 13, connected across the feeder 6 and The secondary of this'transformer is divided into two coils, 14, 15. coil 14 is connected to. the coil 11, of the thermo-generator, and the coil 15 is connected at one end to contact plate 16, and at the other end to an arm, 17, on the armature of relay 18. The coil 15 includes a solenoid, 1-9, in which the core 20, connected to the signal, moves. The relay 18 is located, as is usual, at the op osite end of the. block'from that atwhich t e difference of potential'is created. It is connected across the rails 7, 8 of a block, the direct current generating device and the relay thus forming a closed ciris to counteract the effect of any alternating current which would pass from the .trac

rails into the fixed andmovable members of the-relay, and which would tend to rotate the relay in the absence of'such coil:- The theoretical considerations involved are as follows: The short-circuited coil, 25, tends I closed iron tube 34 forms a magnetic ath to exclude any alternating magnetic flux which might be set up by alternatlng current in coil 23 on account ofthe induced currents set up in such short circuited coil, and which act as counter-magneto motive forces, opposin the alternating magneto-motive force of coi '23. Also, the coil 25, owing to its induced currents will exert a counter torque, so as to further neutralize the rotative eflort,

due to the alternating current traversing coils 23 and 24. It will of course be evident that the direct current and magnetic flux after they are once established, will not be afiected by the action of the coil 25.

In Fig. 4 both tr'aflic rails are divided into block sections by insulators 9. In this case the rail 7 of one section is connected through a conductor, 26, to the rail 8 of the next sec' tion, reversing from block to block, so that instead of the rail 8 acting as the. return for the propulsion current, as in Fig. 1, sections ofrails -7 and 8 act as the return for the propulsion .current. In this figure, as before stated, a battery, 27, is substituted for the thermo-generator as a means for exciting a direct current diflerence of. potential between the rails and 8. Further, instead of using thejrelay 18, I may use the relay 30,

which, while it corresponds in principle with the relay 18 so far as relates to being oper able only by a direct current,is different in construction. This relay consists, of an iron core, 31, preferably not laminated, surrounded'by. a copper shield, 32, and a coil, 33, connected across the trackway. Thecoil 33 may be surrounded by an iron tube, 34, and a movable member, 35, which consists of an iron core, 36, surrounded by a copper shield, 37, and carrying a depending contact plate, 38, adapted to cont-act with the contact plates 39, 40. v

Figs. 6 and 7, show a modified form of the relay 30, where, instead of using a single core, 31, three cores 41, 42, and 43, are employed. In this form of relay, a resistance, 44, is placed'in circuit of the coil surrounding the core43, and is designed to displace the phase of any alternating current flowing through this coil tromthe alternating current flowing in can; 41

.The term of'relay shown in Fig. 6 has the advantage, by reason of'the arrangement of its cores, of reventingchattering of the movable mem er 35. The theoretical considerations involved are as follows:

T he'shield 32 is in the form of a short circuited coil which may be of any desired number. of turns. If an alternating current flowed in the coil 33, it would normally pro duce an alternating magnetic flux, but the coil 32, which is short circuited will then develop induced currents, which act as counter magneto-motive forces effectively damping out any alternating magnetism. The

closed on itself and surrounding the coi 33, so that any alternating current in such coil' will set up an oscillating magnetic flux in the iron tube, producing thereby a counter electro-motive force in the windings of the coil 33, thereby tending to exclude any alternating current from' such coil. The action of the tube 34 is the same substantially as the insertion of reactanc-e in series; with the coil 33, and it will be obvious that a reactance could be connected in series with the coil 33 if desired. The reactance effect described is, of course, not essential. The shield, 37, is similar in its action to the shield 32. It is some times found that an alternating magnetic flux not suflicient to actuate therelay may, however, occasion a chattering of the contact.

different branches of, the magnetic circuit. For this reason, in Fig. 6, the phase of the magnetic,fluxes is made diflercnt in the coils 41, 42, and 43. On account of such difi'erence'in phase the tractive effort due to the alternating current is rendered more even, thereby doing away with any chattering.

The general operation of my system is as follows: When a car is in a block, the wheels of the car short circuit the relay, and the signal being counter-weighted goes to the danger positirm, the position of the relay being that shown at Z, Figs. 1 and 4.

Vi/ hen. a car leaves a block, the direct current impressed upon the block flows through the relay, rotates the movable member, Fig. 1, or elevates the movable member, Fig. 2, and .thus closes the circuit through the secondary coil 15 oi" the transtormer 9, which by solenoid 19 attracts core 20, and moves the signal to the clear position, as illustrated in blocks X and Y, Figs. 1 and 2.

I wish it understood that I do not limit myself. to the particular arrangementof the trackway described, or the special-construction shown for the relays, as various modifications may be made. Thus I may employ both rails of the trackway for the return of the propulsion current, in which case the resistance of the translatin device, 18, Fig. 1, would be made low an also that of the source of E. M. F. energizing the block sec-- tion. Similarly, where one rail alone is used for the return of the propulsion current, rcactances might be inserted both in series with the source of E. M. F at the energy end andwith the translating device at the opposite end of the block section. Various methods of connecting the elements of the system will at once occur to those skilled in the art. Also I may vary the arrangement of the system as by using a direct current for heating the thermo-generator and actuating the signals. Generally, I wish to have it understood that I consider myself to be the first to described This isobviatedby causing such magnetic flux to have a different phase in l. 0 ii relay and the use of a relay in a signaling system,'which, while susceptible to the flow of g which are traversed by the power current on .its return to the generator, means for exciting a direct current difference of otential between the railsof each block, an a relay connected across the rails of each block operable by direct current but not by the alternat ing power current.

2. A signaling system comprising a source of alternating power current, a trackway divided into block sections, both of the rails of which are traversed by the'power current on its return to the generator, means for exciting a direct current difference of potential between the rails of each block, and a relay connected across the railsof each block operable b direct current but shielded from the alternating power current,

- divided into block sections, both of the rai s 3. A signaling system comprising a source of alternating power current, a trackway divided into block sections, both of the rails of which are traversed by the power current on its return to the'generator, means for exciting 'a direct current difference of potential between the rails of each block, a'relay in each block having its field, and armature directly connected across the rails of the blr- :k and said relay operable by a direct current but not by an alternating current.

4. A signaling system comprising a source of alternating power current, a trackwa of which are traversed by the power current on its return to the generator, means for exciting a direct current difference of potential between the rails of each block, and a rota relay connected across the rails of each bloc operable by direct current but not by alternating power current.

5. A signalingsystem involving block sections, comprising an alternating current generator for the propulsion current, thermogenerators for exciting a direct current'dife; 'fercnce of potential between the. rails of the bl'ocl sections, and a translating device energized by the direct current in each block section.

6. A signaling system involving bldck'ec: f t ons, comprising an a ernating current generator for the propulsion current, a thermogenerator in each block for creating a direct current difference of potential between the.

rails and consisting of a series of bars of'disslnnlar metal ,connectedtogether and'cone nected across the trackway, with means for heating the joints, and a translating device in each bloclg section energized by the current derived from said thermo-generators. but unaffected by the current from the alternatin current generator."

7. i signaling system comprising a source of alternating power current, a trackway divided into block sections, both ofth'e rails of which are traversed by the power current on its return to the generator, means for exciting a direct current difference of potential between the rails ,of each block, and a relay connected across the rails of each book traversed both by the ower current and said direct current, toget er with means for nullifying the effect of the p'oweifcurrentlon the relay.

8. A signaling-system comprising a source of alternating power current, a trackway-divided into closed-circuited block sections, both of the rails of which are traversed. by the power current on its return to the generator, means for exciting a direct current difference-of potential atone end of each block, and a relay connected across the: rails at the opposite end of each block operable by the direct current only.

9. A signalingsystem comprising, a source of alternatingpower current,.a trackway divided into closed-circuited block sections, both of the rails of which are traversed by' the power current on its return to the generator, means for exciting a direct current difference of potential at one end of each block, and a selective relay device at-the other end of each block section, said relays normally actuated by the difierenceof potential across the rails of the block in which they are included. Y I H I 10. A signalingsystem comprising a-source. of alternating power current, a trackway divided into closed-circuited block sections, both of the rails of which are'traversed by the power current on its return to the generator, means for excitinga direct current difference of potential at one end of each block, a selective relay connected across theopposite end of eachblock, and means for sh ielding-said relays from the eflect of any current other than that due to the difference of potential between the rails of they are included. p

1 1. Asignaling system comprising a source of alternating power current, a source of direct signaling current, closed-circuited block sections, both ofthe rails of which are traversed by. the power current on its, return to the generator, and relaysoperable only by the direct signaling current.

the block in which 12. In a signaling systemof the type described, a signal controlling device normally energized by the'direct current, means for shielding it fromthe actionof alternating .current, and nieansfor'preventing chattering of the movable member of such device. 13. A I signal ng system comprising a source of alternating power current, a trackway divided into closed-circuited block sec:- tions, both of the rails of which are traversed by the power current on .its return to the generator, means for exciting a direct current difference of potential between. 'the rails of each block, and a relay connected across the rails of each blockooperable by direct" current but not by the alternating power current.

14. A system of signaling comprising a source of alternating power current, 'a' track- Way divided into clo'sedgcircuited block sections. bdthofzthe rails of which are traversed I by the power current on its return to the generator, means for. impressing a. direct current upon the rails of the block sections, and a relay connected across the rails of each block section operablev only by said impressed current.

source of alternating power current, track rails divided into block sections, cross bonds in each block section, means excited by the power current for exciting a direct current difference or" potential between the rails, and

current diiierence of potential between the rails, and arelay connected across the rails of each block operable by direct current only.

1-7. A signaling system comprising a source of alternating power current, a-trackway divided-into closed circuited block sec tions, both of the rails ofwhich are traversed by the power current on its return to the generator, means for excitin' a direct current difierence of potential located at one end of each block section, and. a relay connected across the rails at the opposite end of each block section, and a signal controlled .by said. relay.

18. A signaling system. comprising a source of alternating power current, a feeder therefrom,. a 'trackway divided into block sections, athermo generator bond connected across the' trackway, a transformer connected across the feeder conductor and one rail and havin a divided secondary, oneportron connecte to acoil on the thermobond and the other portion to the terminals'of .a local circuit, and a relay connected across the'rails of each. block operable by said direct current and adapted to normally close the terminals of the local circuits to carry signals to the clear positlon.

asystem of automatic signaling,

h trolled by said 15. A signaling system compr sing a the combination of sources of direct current source of alternatin powercurrent, a trackway divided into b ock sections, meansfor exciting a direct current difference of potentialibetween the rails of each block section,

a relay. connected across the rails of eachblock section said relay comprising a fixed member having a coil thereon and a movable member having a coil thereon in series with the coil of the fixed member and acloscd-circuited coil, thecoils which are in series trav-. ersed by a irect and an alternating current, andthe closed-.circuited coilhaving a cur-- rent induced therein by the alternating ourrent traversin the series coil, andsignals conrelays.

21-. In a signalin system wherein the power current is an a ternating current flowing along the rails and the signaling current a direct current impressed upon the rails, re; lays comprising two members, one fixed and the other .movable, each of said members having a coil in series with a coilof the other member and connected across thetrackway and the movable member havim' a closed-. circuited coil, and signals controlled by said relays.

22. In a signalin system wherein the power current is an a ternatingcurrent flowing along the rails and the signaling current a direct current impressed upon the rails, relays connected across the track rails through the members of which both currents flow, and a closed-circuited coil on the movable member of the'relays adapted to nullify the influence of the alternating current flowing through said relays, andsignals actuated by said relays.

23. In a signaling system wherein the power currentis an alternating current flowing along both rails-of the trackway as a re turn to the source, and where the signaling current is a direct current creating a difierenceof potential between the rails, a relay adapted to be traversed by said power current and signaling current, but to be actuated only b the direct current, together with means or neutralizing the effect of the power current transmitted.

. f 24. A signaling system comprisin a source of alternating power current, a trac way divided into block sections, a thermo bond-in each block section, .means for exciting said thermo bond'to produce a direct cin'rent difference of potential between the rails of each block, and a relay connected across the rails of each block traversed by the power current and by the direct current, to ether with means 'for' neutralizing the e ect of the power current transmitted through the relay.

25.- A- system comprising a source of alternating power current, a trackway dii'ided into block sections, said trackway forming a return for the power current and having an alternating difference of potential due to the power current. means for exciting a direct current difference of potential be tween the rails, and relay devices through which both the power current and the direct current are flowing, together with means for neutralizing the effect of the power current,

- and signals controlled by said relays.

26; A signaling system wherein there is an alternatmg diiference and a direct current difference of potential between thrails due In testimony thereof, I aflix my signature, i 20 in the presence of two witnesses.

FITZHUGH TOWNSEND.

W'itnesses FRANK OCoNNoR, M. G. CRAWFoR'bf 

